summaryrefslogtreecommitdiffstats
path: root/drivers/s390/char/sclp_sdias.c
blob: 50f7115990fffc3954cc99f24bdd06d1caa4fa7a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
/*
 * Sclp "store data in absolut storage"
 *
 * Copyright IBM Corp. 2003,2007
 * Author(s): Michael Holzheu
 */

#define KMSG_COMPONENT "sclp_sdias"
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt

#include <linux/completion.h>
#include <linux/sched.h>
#include <asm/sclp.h>
#include <asm/debug.h>
#include <asm/ipl.h>

#include "sclp.h"
#include "sclp_rw.h"

#define TRACE(x...) debug_sprintf_event(sdias_dbf, 1, x)

#define SDIAS_RETRIES 300
#define SDIAS_SLEEP_TICKS 50

#define EQ_STORE_DATA	0x0
#define EQ_SIZE		0x1
#define DI_FCP_DUMP	0x0
#define ASA_SIZE_32	0x0
#define ASA_SIZE_64	0x1
#define EVSTATE_ALL_STORED	0x0
#define EVSTATE_NO_DATA		0x3
#define EVSTATE_PART_STORED	0x10

static struct debug_info *sdias_dbf;

static struct sclp_register sclp_sdias_register = {
	.send_mask = EVTYP_SDIAS_MASK,
};

struct sdias_evbuf {
	struct	evbuf_header hdr;
	u8	event_qual;
	u8	data_id;
	u64	reserved2;
	u32	event_id;
	u16	reserved3;
	u8	asa_size;
	u8	event_status;
	u32	reserved4;
	u32	blk_cnt;
	u64	asa;
	u32	reserved5;
	u32	fbn;
	u32	reserved6;
	u32	lbn;
	u16	reserved7;
	u16	dbs;
} __attribute__((packed));

struct sdias_sccb {
	struct sccb_header  hdr;
	struct sdias_evbuf  evbuf;
} __attribute__((packed));

static struct sdias_sccb sccb __attribute__((aligned(4096)));
static struct sdias_evbuf sdias_evbuf;

static DECLARE_COMPLETION(evbuf_accepted);
static DECLARE_COMPLETION(evbuf_done);
static DEFINE_MUTEX(sdias_mutex);

/*
 * Called by SCLP base when read event data has been completed (async mode only)
 */
static void sclp_sdias_receiver_fn(struct evbuf_header *evbuf)
{
	memcpy(&sdias_evbuf, evbuf,
	       min_t(unsigned long, sizeof(sdias_evbuf), evbuf->length));
	complete(&evbuf_done);
	TRACE("sclp_sdias_receiver_fn done\n");
}

/*
 * Called by SCLP base when sdias event has been accepted
 */
static void sdias_callback(struct sclp_req *request, void *data)
{
	complete(&evbuf_accepted);
	TRACE("callback done\n");
}

static int sdias_sclp_send(struct sclp_req *req)
{
	int retries;
	int rc;

	for (retries = SDIAS_RETRIES; retries; retries--) {
		TRACE("add request\n");
		rc = sclp_add_request(req);
		if (rc) {
			/* not initiated, wait some time and retry */
			set_current_state(TASK_INTERRUPTIBLE);
			TRACE("add request failed: rc = %i\n",rc);
			schedule_timeout(SDIAS_SLEEP_TICKS);
			continue;
		}
		/* initiated, wait for completion of service call */
		wait_for_completion(&evbuf_accepted);
		if (req->status == SCLP_REQ_FAILED) {
			TRACE("sclp request failed\n");
			continue;
		}
		/* if not accepted, retry */
		if (!(sccb.evbuf.hdr.flags & 0x80)) {
			TRACE("sclp request failed: flags=%x\n",
			      sccb.evbuf.hdr.flags);
			continue;
		}
		/*
		 * for the sync interface the response is in the initial sccb
		 */
		if (!sclp_sdias_register.receiver_fn) {
			memcpy(&sdias_evbuf, &sccb.evbuf, sizeof(sdias_evbuf));
			TRACE("sync request done\n");
			return 0;
		}
		/* otherwise we wait for completion */
		wait_for_completion(&evbuf_done);
		TRACE("request done\n");
		return 0;
	}
	return -EIO;
}

/*
 * Get number of blocks (4K) available in the HSA
 */
int sclp_sdias_blk_count(void)
{
	struct sclp_req request;
	int rc;

	mutex_lock(&sdias_mutex);

	memset(&sccb, 0, sizeof(sccb));
	memset(&request, 0, sizeof(request));

	sccb.hdr.length = sizeof(sccb);
	sccb.evbuf.hdr.length = sizeof(struct sdias_evbuf);
	sccb.evbuf.hdr.type = EVTYP_SDIAS;
	sccb.evbuf.event_qual = EQ_SIZE;
	sccb.evbuf.data_id = DI_FCP_DUMP;
	sccb.evbuf.event_id = 4712;
	sccb.evbuf.dbs = 1;

	request.sccb = &sccb;
	request.command = SCLP_CMDW_WRITE_EVENT_DATA;
	request.status = SCLP_REQ_FILLED;
	request.callback = sdias_callback;

	rc = sdias_sclp_send(&request);
	if (rc) {
		pr_err("sclp_send failed for get_nr_blocks\n");
		goto out;
	}
	if (sccb.hdr.response_code != 0x0020) {
		TRACE("send failed: %x\n", sccb.hdr.response_code);
		rc = -EIO;
		goto out;
	}

	switch (sdias_evbuf.event_status) {
		case 0:
			rc = sdias_evbuf.blk_cnt;
			break;
		default:
			pr_err("SCLP error: %x\n", sdias_evbuf.event_status);
			rc = -EIO;
			goto out;
	}
	TRACE("%i blocks\n", rc);
out:
	mutex_unlock(&sdias_mutex);
	return rc;
}

/*
 * Copy from HSA to absolute storage (not reentrant):
 *
 * @dest     : Address of buffer where data should be copied
 * @start_blk: Start Block (beginning with 1)
 * @nr_blks  : Number of 4K blocks to copy
 *
 * Return Value: 0 : Requested 'number' of blocks of data copied
 *		 <0: ERROR - negative event status
 */
int sclp_sdias_copy(void *dest, int start_blk, int nr_blks)
{
	struct sclp_req request;
	int rc;

	mutex_lock(&sdias_mutex);

	memset(&sccb, 0, sizeof(sccb));
	memset(&request, 0, sizeof(request));

	sccb.hdr.length = sizeof(sccb);
	sccb.evbuf.hdr.length = sizeof(struct sdias_evbuf);
	sccb.evbuf.hdr.type = EVTYP_SDIAS;
	sccb.evbuf.hdr.flags = 0;
	sccb.evbuf.event_qual = EQ_STORE_DATA;
	sccb.evbuf.data_id = DI_FCP_DUMP;
	sccb.evbuf.event_id = 4712;
#ifdef CONFIG_64BIT
	sccb.evbuf.asa_size = ASA_SIZE_64;
#else
	sccb.evbuf.asa_size = ASA_SIZE_32;
#endif
	sccb.evbuf.event_status = 0;
	sccb.evbuf.blk_cnt = nr_blks;
	sccb.evbuf.asa = (unsigned long)dest;
	sccb.evbuf.fbn = start_blk;
	sccb.evbuf.lbn = 0;
	sccb.evbuf.dbs = 1;

	request.sccb	 = &sccb;
	request.command  = SCLP_CMDW_WRITE_EVENT_DATA;
	request.status	 = SCLP_REQ_FILLED;
	request.callback = sdias_callback;

	rc = sdias_sclp_send(&request);
	if (rc) {
		pr_err("sclp_send failed: %x\n", rc);
		goto out;
	}
	if (sccb.hdr.response_code != 0x0020) {
		TRACE("copy failed: %x\n", sccb.hdr.response_code);
		rc = -EIO;
		goto out;
	}

	switch (sdias_evbuf.event_status) {
		case EVSTATE_ALL_STORED:
			TRACE("all stored\n");
		case EVSTATE_PART_STORED:
			TRACE("part stored: %i\n", sdias_evbuf.blk_cnt);
			break;
		case EVSTATE_NO_DATA:
			TRACE("no data\n");
		default:
			pr_err("Error from SCLP while copying hsa. "
			       "Event status = %x\n",
			       sdias_evbuf.event_status);
			rc = -EIO;
	}
out:
	mutex_unlock(&sdias_mutex);
	return rc;
}

static int __init sclp_sdias_register_check(void)
{
	int rc;

	rc = sclp_register(&sclp_sdias_register);
	if (rc)
		return rc;
	if (sclp_sdias_blk_count() == 0) {
		sclp_unregister(&sclp_sdias_register);
		return -ENODEV;
	}
	return 0;
}

static int __init sclp_sdias_init_sync(void)
{
	TRACE("Try synchronous mode\n");
	sclp_sdias_register.receive_mask = 0;
	sclp_sdias_register.receiver_fn = NULL;
	return sclp_sdias_register_check();
}

static int __init sclp_sdias_init_async(void)
{
	TRACE("Try asynchronous mode\n");
	sclp_sdias_register.receive_mask = EVTYP_SDIAS_MASK;
	sclp_sdias_register.receiver_fn = sclp_sdias_receiver_fn;
	return sclp_sdias_register_check();
}

int __init sclp_sdias_init(void)
{
	if (ipl_info.type != IPL_TYPE_FCP_DUMP)
		return 0;
	sdias_dbf = debug_register("dump_sdias", 4, 1, 4 * sizeof(long));
	debug_register_view(sdias_dbf, &debug_sprintf_view);
	debug_set_level(sdias_dbf, 6);
	if (sclp_sdias_init_sync() == 0)
		goto out;
	if (sclp_sdias_init_async() == 0)
		goto out;
	TRACE("init failed\n");
	return -ENODEV;
out:
	TRACE("init done\n");
	return 0;
}

void __exit sclp_sdias_exit(void)
{
	debug_unregister(sdias_dbf);
	sclp_unregister(&sclp_sdias_register);
}